1. Field of the Invention
The present invention relates to a door opening/closing device that detects abnormality in which a foreign matter is caught in a door.
2. Description of the Related Art
Conventionally, a device for opening and closing a sliding door of a vehicle includes a pinch detecting device. The pinch detecting device detects an abnormality in which a foreign matter is caught in a door. The pinch detecting device includes a door driving unit that has a motor, a load detecting unit that detects a load on the motor, a position detecting unit that detects a position of the door, a storing unit that stores data on the load in association with a sampling area addressed according to the position of the door, a updating unit that updates the data every time the data is read out for an address of a latest sampling area, and an estimating unit that reads out data on the load of a sampling area that is an appropriate number of areas ahead of a sampling area where the door is actually present, and that estimates a load on the motor for moving the door, based on read data and data on a load of the sampling area where the door is actually present. The abnormality is detected based on a deviation between estimated load and the load of the sampling area where the door is actually present (for example, Japanese Patent Application Laid-Open No. H9-125823).
Conventionally, such abnormality, in which a foreign matter is caught in a door, is detected based on a deviation in a load on a motor, which is a deviation in a current. To improve detection accuracy, a threshold for detecting the abnormality should be lowered. However, when the threshold is lowered, the pinch detecting device can erroneously detect a load caused due to other reasons, such as a resistance to movement of a door, as such abnormality.